The Effect of Subconjunctival Injection of Bevacizumab After Resection of Muscle in Rabbit Models

ABSTRACT

PURPOSE: To study the effects of subconjunctival injection on the conjunctiva and muscles after muscle resection in a rabbit model. METHODS: Resection surgery of 5 mm was performed on both the superior rectus muscle (SR) and the inferior rectus muscle (IR) in five white rabbits. As such, 2.5 mg bevacizumab was subconjunctivally injected around the right SR and IR in the experimental group. The left eyes were not injected and were instead used as the control group. The degrees of injection and edema of conjunctiva were classified on a scale from 0 to 4 via gross examination by five examiners at two and four weeks after surgery. The strength of the muscle attachment was assessed, and the degrees of conjunctival inflammation and inflammation and fibrosis of the muscle were classified on a scale from 0 to 4 at four weeks after surgery via histologic examination. RESULTS: The results of gross examination at two and four weeks after surgery showed positive correlation among the five examiners (k=0.52, k=0.4), although there was no statistically significant difference between the experimental and control groups (p=0.285, p=0.364). There was also no significant difference between the two groups with regard to tensile strength of the attachment (p=0.414), inflammation of the conjunctiva and muscle, or fibrosis of the muscle in histologic examination (p=0.698, p=0.702, p=0.232, respectively). CONCLUSIONS: There were no significant effects on the inflammation and fibrosis of the conjunctiva or muscles due to subconjunctival injection of 2.5 mg of bevacizumab after muscle resection in a rabbit model.